package main

import (
	"bufio"
	"fmt"
	"os"
)

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Scan()
	line := sc.Text()
	for i := range line {
		if int(line[i])-(i+1)%26 < int('A') {
			fmt.Print(string(int(line[i]) - (i+1)%26 + 26))
		} else {
			fmt.Print(string(int(line[i]) - (i+1)%26))
		}
	}
	fmt.Println()
}